Salvage methods and apparatus

ABSTRACT

A system of processing material involves cutting pieces of material pursuant to a cut list and managing remaining salvage and defect pieces.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority under 35 U.S.C. § 119 andapplicable foreign and international law of U.S. Provisional PatentApplications Serial Nos. 60/405,067 and 60/405,069 filed Aug. 20, 2002,each of which is hereby incorporated by reference in its entirety.

[0002] This application incorporates by reference in its entirety thefollowing U.S. patent applications and patents: U.S. patent applicationSer. No. 09/578,806 filed May 24, 2000 entitled “Automated Fence ControlCoupling System”; U.S. patent application Ser. No. 09/861,231 filed May17, 2001 entitled “System and Method of Marking Materials for AutomatedProcessing”; U.S. patent application Ser. No. 10/104,492 filed Mar. 22,2002 entitled “Automated Fence Control Coupling System”; U.S.Provisional Patent Application Serial No. 60/405,068 filed Aug. 20, 2002entitled “Process Management System and Method”; and U.S. Pat. Nos.491,307; 2,315,458; 2,731,989; 2,740,437; 2,852,049; 3,994,484;4,111,088; 4,434,693; 4,658,687; 4,791,757; 4,805,505; 4,901,992;5,251,142; 5,443,554; 5,444,635; 5,460,070; 5,524,514; and 6,216,574.

FIELD OF THE INVENTION

[0003] The invention involves systems and methods of processingmaterial, particularly relating to salvage and waste management.

BACKGROUND OF THE INVENTION

[0004] Automated saws are used extensively to cut materials for manydifferent manufacturing applications. For example, saws may use amicroprocessor to determine how to cut according to a user-supplied listof required dimensions, i.e., a cut list. The microprocessor controlsmovement of a pusher to position sites of cutting in a manner thatoptimizes utilization of raw material. For some applications, theoperator may need to mark defects, such as knots, cracks, or discoloredportions of a material, before cutting. The marked locations of defectsallow the microprocessor to select cutting sites that exclude defectswhile making optimal use of the material according to the cut listrequirements. However, a problem with existing systems is that after,cutting remaining pieces not conforming to the cut list are too oftenwasted.

SUMMARY OF THE INVENTION

[0005] The invention includes numerous aspects and permutations. Forexample, in a method of cutting material, a computer is connected to asaw machine. The computer is programmed to optimize cutting of stock tosatisfy a cut list. Initially, a cut list is entered into the computer,along with a minimum salvage length (Smin), a minimum defect length(Dmin), and a maximum drop box length (DBmax). The length of a piece ofmaterial to be processed in input into the computer. Next, locations ofthe defects in the material are input into the computer. The computerthen determines a cutting plan in which: (a) salvage pieces havinglength less than Smin are cut to length as DBmax or less, and (b) defectpieces having a length less than Dmin are cut to lengths of DBmax orless; except if adjacent salvage and defect pieces have a combinedlength greater than Dmin then the adjacent pieces are not cut to DBmaxor less regardless of their individual length.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006]FIG. 1 is a view of an automated processing system including avirtual marking assembly, in accordance with aspects of the invention.

[0007]FIG. 2 is a schematic side elevation view of the virtual markingassembly of FIG. 1 showing a default optical path.

[0008]FIG. 3 is a schematic side elevation view of the marking assemblyof FIG. 2 with an object marking a proximal boundary of a featurelocation by creating a new optical path.

[0009]FIG. 4 is a schematic side elevation view of the marking assemblyof FIG. 2 with an object marking a distal boundary of a feature locationby creating a new optical path.

[0010]FIG. 5 is a schematic side elevation view of a marking systemaccording to another embodiment of the invention.

[0011]FIG. 6 is a schematic view of a marking system according to yetanother embodiment of the invention.

[0012]FIG. 7 is a schematic view of an automated material processingsystem, in accordance with an embodiment of the invention.

[0013]FIG. 8 shows a flow chart illustrating a method of salvagingmaterial.

[0014]FIGS. 9 and 10 show side views manufacturing assemblies configuredfor double ended processing.

DETAILED DESCRIPTION OF EXAMPLES OF THE INVENTION

[0015] An example of an automated processing system constructed inaccordance with the present invention is shown generally at 10 inFIG. 1. System 10 includes a marking assembly 12 positioned along afront portion of the system. Marking assembly 12 includes a markingstation 14 to orient an article or material 16 relative to an opticalmeasuring device 18. The article may be a wood product, metal, plastic,ceramic, and/or the like. The article may have any suitable shape andsize, and may be elongate to define a long axis, which also may be aprocessing axis.

[0016] Feature locations 20 along a processing axis 22 of material 16may be input by a user to the optical measuring device 18, whichcommunicates the feature locations to a controller 24. Another computer24 a may be used remotely from controller 24 to store, edit, combine, ormodify cut lists prior to downloading one or more cut lists tocontroller 24. Marking assembly 12 allows a user to virtually markfeature locations 20 of material 16 along processing axis 22 of thematerial. A “virtual mark” means a noted location on a material relativeto a registration point such as an end of the material or an axis,without requiring an actual physical mark on the material.

[0017] Optical measuring device 18 may provide data input forprocessing. The optical measuring device may send a light beam alongoptical path 26. As described in more detail below, this path may bealtered for at least a portion of the light beam by placing an objectinto the light beam at a location corresponding to a perimeter region offeature location 20. Alternatively, the object may be placed at aselected location that inputs data about other structural aspects of thematerial or about nonstructural aspects of material processing.Controller 24 may use one or more structural aspects of the material,such as feature locations 20 and/or overall length, among others, todetermine cutting sites. Structural aspects may include dimensions,defect locations, grade of material, etc. One or more structural aspectsmay be input optically and/or with another user interface.

[0018] Processing station 28 may be configured to process the materialautomatically based on the optically input data. Material processing, asused herein, may include any structural alteration of an article (amaterial). The structural alteration may include removing or separatinga portion of the article (such as by cutting, boring, punching, routing,mortising, sanding, drilling, shearing, etc.), adding another component(such as a fastener, a colorant, a sealing agent, a connected component,etc.), forming a joint (such as by tenoning), reshaping the article(such as by stamping, compression, bending, etc.), and/or altering thestrength of the article (such as by heating, electromagnetic radiationexposure, radiation treatment, etc.), among others.

[0019] Station 28 may include a positioner assembly 29, which mayposition previously-marked material 30, relative to a materialprocessing device, such as a saw 32. Positioned material 30 may beprocessed at one or more discrete positions along processing axis 34 ofmaterial 30 by saw 32. Material processing may be based onvirtually-marked feature locations 20 or other processing data suppliedby the user, by deflecting a light beam, as described below. Materialprocessing also may be in accordance with a processing list, such as acut list, which may be stored in or otherwise accessible to controller24.

[0020] In some embodiments, a material feeding or positioning device 37,such as a roll feeder, may be used to feed material to a materialprocessing device, such as a saw, in processing station 28.Alternatively, a pusher mechanism may be employed to engage an end ofthe material and push the material relative to the processing station,particularly relative to a material processing device of the processingstation. Movement of a material positioning device (and/or a materialprocessing device) along a line defines a processing line for in-lineprocessing of an article. Accordingly, an article may be processed atone position or a plurality of discrete positions arrayed parallel tothe processing line.

[0021] As shown schematically in FIG. 2, optical measuring device 18includes a light source 42 and a light detector 44. Light source 42sends or transmits a light beam 46, produced, for example, by acontinuous or pulsed laser, along default optical path 26 to reflector48, which reflects the light beam back to detector 44. Reflector 48 isan optional component of marking station 12 that provides a defaultoptical path when the user has not interrupted optical path 26.Reflector 48 may be useful for calibrating optical measuring device 18and to assist in positioning and measuring material 16, as describedmore fully below.

[0022] Processing data may be created by optical measuring device 18according to the position at which light beam 46 is deflected manually.The processing data created may be analog and/or digital data.Deflection of a light beam, as used herein, is any deviation produced inat least a portion of the light beam away from a particular direction oftravel, generally along a line. Deflection of the light beam may beproduced by any suitable optical mechanism, including reflection,refraction, diffraction, scattering, and/or the like.

[0023] Detector 44 receives light from light beam 46 and detects anyproperty of the light that allows device 18 to measure the position atwhich the light beam was deflected. For example, the detector maymeasure the length of optical path 26. In some embodiments, detector 44may provide measurement of a time-of-flight of light from light beam 46along optical path 26 by signaling light detection to a clock. The clockmay measure the time-of-flight between light transmission and lightdetection and thus may provide a distance measurement or a related lightparameter to be sent to controller 24 through any suitable means such ascommunications link 50 of FIG. 1. Rather than a time-of-flightmeasurement, any other property of light from light beam 46 may bemeasured to determine distance, such as angle of deflection fortriangulation (see FIG. 6), or a phase shift using an interferometer,among others. Suitable optical measuring devices for use in the presentinvention are available from Leica Geosystems of Herrbrugg, Switzerland,under the name DISTO or from Hilti Corporation of Tulsa, Okla., underthe names PD10 or PD20.

[0024] As shown in FIGS. 1 and 2, processing axis 22 of material 16 maybe positioned substantially parallel to optical path 26, or a portionthereof, as processing data is input by deflection of the light beam.The light beam may be sent from light source 42, at a distance 54 fromdistal end 56 of wood product 16. Light beam 46 may travel along opticalpath 26 in a spaced relation from surface 60, for example, about 2inches above surface 60. As shown in FIG. 2, surface 60 of material 16may be substantially parallel to optical path 26, or a data input linethereof, and may be a top surface or a side surface of material 16.Optical path 26 also may be disposed below a bottom surface of material16 and visualized with an appropriately-positioned mirror or mirrors.

[0025] The long axis and/or processing axis of material 16 may beoriented at least substantially parallel to optical path 26 in markingstation 14, using an appropriate supporting structure such as brackets64. Reflector 48 may act to define the default optical path 26. Aproximal end 66 of material 16 may abut reflector 48. Proximal end 66may be marked optically by deflection of the light beam by reflector 48,or may be manually marked by altering optical path 26, as describedbelow, without the use of reflector 48.

[0026]FIGS. 3-4 show schematically how optical path 26, for at least aportion of the light beam, may be altered by an object marking featurelocations 20 of feature 68 in material 16. Feature 68 may be any aspectof material 16 between proximal end 66 and distal end 56 that may affectprocessing of material 16. For example, when material 16 is a woodproduct, a feature 68 may be a defect such as a knot, crack, recess,discolored portion, or uneven surface aberration. Features also mayinclude proximal end 66 and distal end 56 of material 16. In some cases,a feature 68 may include any structural aspect of material 16 thatinfluences subsequent processing of the material. With a wood product asmaterial 16, feature location 20 typically defines a beginning orboundary location of a clear portion of the wood product that isdefect-free.

[0027] As shown in FIG. 3, proximal end 69 of defect 68 may be marked bymanually placing an object 70 in the light beam. The term manual, asused herein, means employing human rather than mechanical energy, thatis, not automatic. Accordingly, object 70 may be any user-controlledobject capable of deflecting some or all of light beam 46 to detector 44from a position within optical path 26. Since many objects can deflectlight, the choices for object 70 are numerous. For example, object 70may be provided by a portion of the operator's body, such as a hand, afinger, an arm, a leg, a foot, a shoulder, etc. Alternatively, theobject may be distinct from the operator, such as a pen, pointer,paddle, mirror, or the like. Such a distinct object may be grasped by anoperator, connected to any suitable portion of the operator's body, ormay be coupled to the marking assembly. In some embodiments, object 70may be slidable along a track that extends parallel to the light beam,and may be manually placed in the light beam while coupled to the track.

[0028] In the example of FIG. 3, object 70 is positioned above theproximal end 69 of defect 68, at a feature location 20 slightly proximalto defect 68. Interrupted, shortened optical path 74 is measured bydetector 44 and communicated to controller 24. Similarly, distal end 80of defect 68 may be marked by positioning object 70, as shown in FIG. 4,at a point along a default optical path 26 corresponding to distal end80, to produce shortened optical path 78.

[0029] A feature location corresponding to distal end 56 of wood product16 may be marked with object 70, as previously described, or bytemporarily lowering optical measuring device 18, or by slightly liftingdistal end 56 of material 16 above bracket 64 so that material 16 altersoptical path 26. The feature location at distal end 56 also may becommunicated to controller 24 through keypad 86 (see FIG. 1) byinputting a total overall value the dimension of the material asmeasured along processing axis 22.

[0030] Each optical path 26, 74, 78 may include an angle of reflection 0at which light beam 46 is reflected back to detector 44. In someembodiments, a maximum angle of reflection θ at each feature locationmay be less than about 30°, less than about 20°, or less than about 10°.

[0031] A typical session for marking material 16 may be initiated with asignal to controller 24 that the user has material 16 properlypositioned on brackets 64. The signal may be initiated by an inputeither through keypad 86, a switch, such as foot pedal 88, or bydeflecting light beam 46, among others. Controller 24 then may recognizeand interpret data sent by optical measuring device 18 according to anysuitable logical sequence. For example, the user may use object 70 tomark proximal end 66 and distal end 56 of material 16 first, followed byinternal feature locations 20 of one or more defects 68. Alternatively,the user may mark all features 20 in linear order, including one or bothend positions of material 16. Controller 24 then interprets internalfeature locations 20 as flanking a defect 68. Marking station 12 alsomay include an audible and/or visible signal mechanism, such as a bell,buzzer, or light, that informs the user when a feature location alongprocessing dimension 22 has been measured and sent to controller 24. Forexample, light post 89 may be provided to give visible signalscorresponding to data input events such as material marking, based onlight beam deflection.

[0032] Once all feature locations 20 have been communicated tocontroller 24, the user may move second material 16 to processingstation 28, for example, after processing of previously processed firstmaterial 30 (see FIG. 1). Alternatively, a processing station may belocated linearly downstream from marking station 14, so that secondmaterial 16 may be moved parallel to its processing axis to place thesecond material in the processing station 28. After second material 16is moved from the marking station 14, or while it is still in themarking station, the controller may be signaled that a third material isto be marked. The third material may be placed in the marking stationand marked by light beam deflection. Processing of first material 30 andmarking of second material 16 may be controlled concurrently bycontroller 24, for example, by signaling the controller with foot switch88. This signal may activate both positioner assembly 29 and opticalmarking device 18. Alternatively, marking assembly 12 may be disposedsuch that material 16 may be marked and processed without moving thematerial to a distinct processing station.

[0033] In the system shown in FIG. 1, positioner assembly 29 usespositioner 106 to push first material 30 along processing line 108.Positioner 106 is any structure that determines the position of material30 along processing line 108. Examples of positioner 106 include apusher, a fence, or a stop block or any other similar structureconfigured to move or index material. Typically, the user placesmaterial 30 in processing station 28, on infeed table 110, so thatprocessing axis 34 of material 30 is parallel with processing line 108of positioner 106, by abutment with guide rail 112. Positioner 106 movesparallel to processing line 108 to contact distal end 114 of woodproduct 30. Positioner 106 positions proximal end 116 of wood product 30an appropriate distance beyond saw 32 based on a positioning signal sentfrom controller 24 to a motor in housing 118. The motor controlsmovement of positioner 106 through slider 120 in positioner assembly 29.Slider 120 is displaced along guide rail 112 in response to controller24 instructions to the motor. Alternatively, instead of a pushing-typepositioner to move material 30 to the saw, the saw may be automaticallymoved along the processing line to an appropriate location for cuttingaccording to marked features. In another design, a roll feeder may beused to move the material.

[0034] After positioner 106 has automatically positioned wood product 30appropriately, saw 32 is activated to process wood product 30. This maybe carried out automatically, for example, by controller 24 moving saw32, or manually, by the user moving saw 32. In an alternativeconfiguration, movement of material 30 relative to modifying device 32may be achieved also by moving device 32 parallel to processing axis 34,while material 30 is kept stationary. It should be noted that themarking station 12 may be useful with any automated processing system inwhich materials to be processed include features 68 that vary inlocation between the materials along processing axis 22.

[0035] After material 30 is cut, it may continue downstream onto outfeedtable 121. Drop-box hole 121 a may be provided in outfeed table 121 toallow waste pieces to fall into a waste receptacle.

[0036]FIG. 5 shows a marking system 200 according to an alternateembodiment of the invention. Light source 202 directs light beam 204 toreflector 206 where the beam is reflected to detector 208. Bumper 210maintains material 212, at a fixed location relative to fixed light beam204. Portion 214 of light beam 204 between bumper 210 and reflector 206can be used to create signals by interrupting beam portion 214. Thesignals may be interpreted by a computer, for example, as processinginstructions, separate from marking steps on material 212. This designenables many possible functions and adaptations to system 200. Forexample, a virtual keyboard 216 may be created. A template or similardevice may be positioned near beam portion 214 so that operator maypoint to or touch different locations on the template, thereby causinginterruptions of beam 204 at different locations. This feature of theinvention may be used to input processing data or instructions that arerelated to, or distinct from, structural aspects of the material to beprocessed. For example, such data or instructions may signal thebeginning or ending of a structural data input, initiation of materialhandling steps, start and/or stop instructions, the grade of materialbeing processed, processing instructions relative to marks that havebeen or will be indicated on the material, etc.

[0037]FIG. 6 shows a marking system 230 that measures distances based ontriangulation. Marking system 230 may be included in any suitableautomated processing system. Marking system 230 may include an opticalmeasuring device 232 having a light source 202 and a detector 234. Thelight source may send a beam of light 204 along a data input line 236 toa point of reflection, shown at 238 and 240. The point of reflection maybe provided by default reflector 206 or by an object 70 placed in thelight beam at a selected position along the data input line. Defaultreflector 206 or object 70 may reflect only a portion of light beam 204to detector 234, shown at 242 or 244, such as by diffuse reflection.

[0038] The angle defined by the reflected light beam may be measured bydetector 234, to provide a measure of the point of reflection along thedata input line. Suitable optics, such as a lens 246, may be disposedbetween the point of reflection and the detector to focus light beamportions 242, 244 onto detector 234. The position at which each lightbeam portion is detected by detector 234 may be used to calculate thepoint of reflection by triangulation. For example, light beam portion242 forms a smaller angle with data input line 236 than light beamportion 244. Accordingly, each of these angles may be related to a pointof reflection and thus a distance/position along the data input line.

[0039] The data input line is any line segment in which an object may beplaced in the light beam to input data for material processing or systemoperation to the controller. The data input line may have any suitablerelationship to the light source and detection mechanism. The data inputline may be substantially or completely formed by air. The data inputline may be at least substantially parallel to the long axis of material16 and/or parallel to an axis along which the material is to beprocessed, generally at one or more discrete positions. The data inputline may extend from the light source to a default reflector 206.Alternatively, the data input line may be configured to be a subset ofthe line or line segment along which the light beam travels. Forexample, positions on this line or segment of travel that are too closeor too far from the light source may not be recognized for data input.In some embodiments, optical elements, such as lenses or mirrors may beemployed between the light source and the data input line to direct thelight beam along the data input line.

[0040]FIG. 7 shows a schematic view of a system 250 for automatedmaterial processing. System 250 may include a data input station 252, amaterial processing station 254, and a controller 256, among others.

[0041] Data input station 252 may be any mechanism for inputting data tosystem 250 by manual deflection of a light beam. A particular positionat which the light beam is deflected may input data that corresponds tothe particular position. The data may relate to operation of the system,processing a material, etc. The data input station may include anoptical measuring device 258 that provides a light beam. The data inputstation also may define a default optical path 260 followed by the lightbeam. A portion of optical path 260 may provide a data input line alongwhich the light beam travels. The optical measuring device may beconfigured so that placement of an object in the light beam at aparticular position along the data input line inputs data to controller256.

[0042] Material processing station 254 may be any mechanism forprocessing a material of interest. Station 254 may include a positioner264 and a material processing device 266 that provide in-line processingalong a processing line 268. The positioner may be configured to moveparallel to a processing line 268, so that a material moves toward thematerial processing device to select discrete positions of the material,arrayed parallel to the processing line, at which the material isprocessed. Alternatively, or in addition, the material processing devicemay be configured to move to discrete positions of the material arrayedin parallel to processing line 268.

[0043] The material processing station may have any suitable spatialrelationship to the data input station. For example, these stations maybe overlapping, so that the material can be processed directly after thedata is input. Alternatively, these stations may be spaced, so that thematerial is moved to the processing station after data input. Forexample, these stations may be at least substantially parallel, that is,data input line 262 may at least substantially or completely be parallelto processing line 268. The data input station may be disposed in frontof, or behind, the material processing station, when viewed from anormal position of operation by a user. Accordingly, a material may betransferred, manually or automatically, from the data input station tothe material processing station by movement perpendicular to the datainput line and/or processing line. In some embodiments, the data inputline and the processing line of such stations may be spaced so that aperson's arms can transfer the material from the data input station tothe material processing station while the person's feet are stationary,or spaced by a distance of less than about four feet. In someembodiments, the data input and material processing stations may bearrayed lengthwise, so that the stations are disposed on the left andright of each other in relation to a user in a normal position of use.Accordingly, the data input line and the material processing line may besubstantially collinear. The material processing station may be disposedso that the material is moved substantially parallel to the data inputline to position the material in the material processing station.

[0044] Controller 256 may be any device configured to manipulate data.Accordingly, the controller may be a digital processor or othercomputing device. The controller may be operatively connected to opticalmeasuring device 258 and material processing station 254, particularlypositioner 266 and/or material processing device 268. Accordingly, thecontroller may be configured to receive data input by a user through theoptical measuring device. In addition, the controller may be configuredto control operation of the positioner and/or material processingdevice, such as their movement, based on the data.

[0045] Controller 256 may be configured to operate data input andmaterial processing stations concurrently, that is, during overlappingtime intervals. Controller 256 may send and receive signals from thestations at slightly different times, but overall the data input andprocessing operations on two articles may be conducted at the same time.Accordingly, the data input station may input data to the controllerabout a second article or workpiece, while the material processingdevice is processing a first article, based on data previously input tothe data input station. In some embodiments, the controller may beconfigured to store input processing data for two or more articles. Thematerial processing station may be configured to sequentially processthe two or more articles based on the input processing data.

[0046] System 250 may include a user interface 270 to provide amechanism in addition to data input station 252 for inputting data tocontroller 256. User interface 270 may include a keypad, a keyboard, atouchscreen, a touchpad, a mouse, a foot-operated pedal, a voicerecognition system, and/or the like.

[0047] Processing system 250 may be equipped with a printer 272, asshown in FIGS. 1 and 7. The printer may be operated manually orautomatically depending on the application. The printer may beconfigured to print hard copy output related to operation of theprocessing system. For example, when the processing system includes asaw, the controller for the saw may be configured so that yield data isautomatically printed out at the end of executing a cut list. In someembodiments, the printout may summarize: (1) linear feet cut, (2)percentage of usable material, (3) percentage of waste material, and/or(4) total cutting time, among others. In some embodiments, the printermay be configured to print labels. The labels may include any suitableprinted information or indicia, such as stop movements, piece counts,cut lengths, materials, part numbers, job names, and/or other kinds ofinformation. The information can be printed to labels of various sizes,depending on the source of the data and parameters in thecalibration/menu. The labels may be configured to be applied manually bya user of the system, or automatically when the material is processed.

[0048] Many different processing variations of the invention may beused. For example, the system may be programmed to record markssequentially in a single direction, so that if a mark is made in orbehind an area that was already marked, then the computer deletes alldata up to that point allowing for correction and remarking of the area.

[0049] The system may also be programmed to manage handling of materialnot conforming to a cut list.

[0050]FIG. 8 shows a flow chart including steps used to salvagematerial. A computer is used in conjunction with an automated saw systemsuch as one of the ones described above. The computer may be programmedto optimize cutting of stock material to satisfy a cut list, and mayalso be programmed to manage use or disposal of remainder material.

[0051] Generally, there may be two types of remainder material. One typeis referred to as “salvage”. Salvage materials are pieces that do notsatisfy cut list requirements and do not contain marked defects. Forexample, if two five foot pieces are cut from an eleven foot boardpursuant to a cut list, the remaining one foot piece (not required bythe cut list) is considered salvage material. A second type of remaindermaterial is referred to as “defect”. Defect materials are pieces thatcontain defects such as knots or blemishes, particularly defects thathave been actually or virtually marked by the operator.

[0052] In the system and method illustrated in FIG. 8, a computer isprogrammed to optimize and manage salvage or saving of remaindermaterial. In system 500, the first step 504 involves inputting one ormore cut lists, a minimum salvage length (Smin), a minimum defect length(Dmin), and a maximum drop box length (DBmax). Next, pieces of stock orraw material are processed according to the following routine.

[0053] In step 506 the length of a piece of material is input into thecomputer. The length may be measured and input manually by the operator.Alternatively, the length may be automatically measured and entered bypositioning one or more sensors along the processing path. The computermay also be programmed to automatically assume end-cuts of apredetermined dimension will be made prior to figuring the best strategyor plan for cutting the material.

[0054] In step 508 the operator marks the location of defects. Markingmay be carried out by actually marking and scanning the material.Alternatively, the preferred approach is to input location(s) of defectsby “virtually marking” the defects using a light reflection orinterruption technique, for example, such as the methods described aboveinvolving use of a light beam substantially parallel to the processingpath.

[0055] In steps 510 and 512 the computer determines how to cut thematerial considering optimum use of material to satisfy the cut list(s),and how to manage remainder material, i.e., salvage and defectmaterials.

[0056] In steps 514 and 516 cut list pieces, salvage pieces having alength equal to or greater than Smin, defect pieces having a lengthequal to or greater than Dmin, and adjacent segments of salvage anddefect pieces having a combined length equal to or greater than Dmin arecut, labeled, and saved for future use.

[0057] In steps 518 and 520 salvage pieces having a length less thanSmin, and defect pieces having a length less than Dmin, are cut tolengths equal to or less than DBmax, and discarded. A drop box may beprovided with an opening dimensioned to allow disposal only of pieceshaving a length equal to or less than DBmax.

[0058] The controller may also be configured to automatically measure apiece of material prior to cutting. The saw system is equipped with oneor more length sensors. A piece of material is placed in the processingline. A pusher shoves the material forward until it reaches the sensor.The controller calculates the length of the material according to theknown position of the pusher at the time the sensor detected the end ofthe material. The controller then determines how best to cut thematerial based on the length determination and any defect informationentered by the operator.

[0059] The invention may also be programmed for double ended processing.For example, the controller may be programmed to control processing ofmaterial between a saw and a drill press, as shown in FIGS. 9 and 10. InFIG. 9, automated pusher 600 is set up on table 601, and configured topush workpieces either in direction 602 towards upcut saw 604, oralternatively, in the direction of arrow 608 toward drill press 610. Inthe example shown in FIG. 9, each machine 604 and 610, has a dedicatedcontroller 612 and 614, respectively, equipped with a keypad forcontrolling operation of pusher 600 when being used with the respectivemachine. Dedicated interlock devices 616 and 618 are provided to preventoperation of the machine when pusher 600 is in motion. FIG. 10 is thesame as FIG. 9 except a single keypad controller in keypad 620 is usedinterchangeably with the two machines 604 and 610. Keypad 620 is shownin position for use with drill press 610. The keypad is also shown indashed lines in position 620a where it would be used with saw 604. Whenpusher 600 is moving, the respective interlock disables activation ofthe tool. When pusher 600 reaches the target location, then theinterlock re-enables the tool to operate and then counts the strokeagainst the cut list. The appropriate interlock may operate depending onwhich end of the positioner track is designated as the “zero end”.

[0060] In another example of the invention, an automatic back-offfeature is implemented. First, the pusher moves a piece of material topoint A relative to a machine such as a saw. Before cutting thematerial, the pusher moves back a preset distance. Cutting is carriedout. Then the pusher returns to point A before pushing the material tothe next position. The back-off step prevents the pusher from shockingor bumping the material while it is being processed.

[0061] The specific embodiments disclosed and illustrated herein shouldnot be considered as limiting the scope of the invention. Numerousvariations are possible without falling outside the scope of theappended claims. For example, the invention may be implemented innumerous different machine configurations with varying levels ofautomation. The invention may also be used to process many differentkinds of materials including, but not limited to, wood, wood composites,polymeric materials such as PVC, polystyrene, polypropylene,polyethylene, fiberglass, textiles, etc. In addition to cutting, theinvention may be used to carry out other processing steps such asboring, punching, routing, mortising, sanding, drilling, shearing,bonding, sewing, heating, UV curing, painting or graphics application,etc. The subject matter of the invention includes all novel andnonobvious combinations and subcombinations of the various elements,features, functions, and/or properties disclosed herein.

We claim:
 1. A method of cutting material comprising connecting acomputer to a saw machine, the computer being programmed to optimizecutting of stock to satisfy a cut list, inputting into the computer: (a)a cut list, (b) a minimum salvage length (Smin), (c) a minimum defectlength (Dmin), (d) a maximum drop box length (DBmax), inputting thelength of a piece of material to be processed, inputting location of anydefects in the piece of material, determining a cutting plan in which:(a) salvage pieces having a length less than Smin are cut to lengths ofDBmax or less, and (b) defect pieces having a length less than Dmin arecut to lengths of DBmax or less; except if adjacent salvage and defectpieces have a combined length greater than Dmin then the adjacent piecesare not cut to DBmax or less regardless of their individual lengths. 2.The method of claim 1, further comprising cutting pieces according tothe plan.
 3. The method of claim 1, further comprising automaticallyprinting labels for pieces cut for the cut list.
 4. The method of claim1, further comprising automatically printing labels for (a) piecesincluded in the cut list, (b) salvage pieces having a length equal to orgreater than Smin, (c) defect pieces having a length equal to or greaterthan Dmin, and (d) adjacent salvage and defect pieces having a combinedlength greater than Dmin.
 5. The method of claim 1, wherein the piecescut to lengths of DB max or less are directed to a waste receptacle fordestruction or chipping.
 6. The method of claim 1, wherein the step ofinputting location of any defects is performed without actually markingthe material to be cut.
 7. The method of claim 1, wherein the step ofinputting location of any defects includes interrupting a light beamnear a defect boundary.
 8. The method of claim 7, wherein the step ofinputting location of any defects includes interrupting a light beam atleast twice indicating upstream and downstream sides of a defect.
 9. Amethod of cutting material comprising connecting a computer to a sawmachine, the computer being programmed to optimize cutting of stock tosatisfy a cut list, inputting into the computer: (a) a cut list, (b) aminimum salvage length (Smin), (c) a minimum defect length (Dmin), (d) amaximum drop box length (DBmax), inputting the length of a piece ofmaterial to be processed, inputting location of any defects in the pieceof material, determining a cutting plan in which: (a) salvage piecesless than Smin are cut to lengths of DBmax or less, and (b) defectpieces less than Dmin are cut to lengths of DB max or less.
 10. Themethod of claim 9, wherein if adjacent salvage and defect pieces have acombined length greater than Dmin then the adjacent pieces are not cutto DBmax or less regardless of their individual lengths.
 11. The methodof claim 9, further comprising automatically printing labels for piecesincluded in the cut list, salvage pieces having a length equal to orgreater than Smin, and defect pieces having a length equal to or greaterthan Dmin.
 12. The method of claim 11, further comprising automaticallyprinting labels for adjacent salvage and defect pieces having a combinedlength equal to or greater than Dmin.
 13. The method of claim 9, whereinthe step of inputting location of any defects is performed withoutactually marking the material to be cut.
 14. The method of claim 9,wherein the step of inputting location of any defects includesinterrupting a light beam near a defect boundary.
 15. The method ofclaim 14, wherein the step of inputting location of any defects includesinterrupting a light beam at least twice indicating upstream anddownstream sides of a defect.
 16. A method of cutting materialcomprising providing a computer programmed to optimize cutting of stockto satisfy a cut list, connecting a computer to a saw machine, thecomputer being programmed to optimize cutting of stock to satisfy a cutlist, inputting into the computer: (a) a cut list, (b) a minimum salvagelength (Smin), and (c) a minimum defect length (Dmin), inputting thelength of a piece of material to be processed, inputting location of anydefects in the piece of material, determining a cutting plan in which:(a) salvage pieces having a length less than Smin are discarded, and (b)defect pieces having a length less than Dmin are discarded; except ifadjacent salvage and defect pieces have a combined length greater thanDmin then the adjacent pieces are saved regardless of their individuallengths.
 17. The method of claim 16 further comprising inputting amaximum drop box length (DBmax) into the computer, and cutting discardedpieces into lengths equal to or less than DBmax.
 18. An apparatus forcontrolling material processing comprising a saw machine, and a computerconnected to the saw machine, the computer being programmed to controloptimized cutting of stock to satisfy a cut list, and saving ofremaining material including salvage pieces having a length equal to orgreater than a preselected Smin, and defect pieces having a length equalto or greater than a preselected Dmin.
 19. The apparatus of claim 18wherein the saw machine includes a pusher configured to push a piece ofmaterial toward a saw under control of the computer.
 20. The apparatusof claim 18, wherein the computer is also programmed to control savingof remaining material including adjacent salvage and defect pieces havea combined length greater than Dmin.
 21. The apparatus of claim 18,wherein the computer is also programmed to control automatic printing oflabels for pieces cut pursuant to the cut list and saved material.